There are approximately 100,000 avalanches each year in the U.S. alone, resulting in at least 200 people being trapped, of which approximately half are killed or injured. Death is most commonly from asphyxiation, with survival time typically being less than 30 minutes. Survival diminishes with increasing burial depth, but average depth is only a foot or two under the snow. Nevertheless, it is difficult to find victims, even with currently available techniques, including probing from the surface and/or using transmitters.
In view of the forgoing, it would be desirable to develop an effective avalanche rescue device.